Page 227 - index

ɋɨɧɵɦɟɧ, ɠԝɦɵɫɬɵԙ ɬɚԙɛɚɫɵ M ɛԝɪɵɲɵɧɚ ɬԥɭɟɥɞɿ, ɹԑɧɢ ɛԝɪɵɲ ɫԛɣɿɪ

ɛɨɥɫɚ, ɨɧɞɚ ɠԝɦɵɫɬɵԙ ɬɚԙɛɚɫɵ ɨԙ (ɩɥɸɫ), ɚɥ ɛԝɪɵɲ ɞɨԑɚɥ ɛɨɥɫɚ, ɨɧɞɚ
ɠԝɦɵɫɬɵԙ ɬɚԙɛɚɫɵ ɬɟɪɿɫ (ɦɢɧɭɫ) ɛɨɥɚɞɵ. Ȼԝɪɵɲɬɵԙ ɬԥɠɿɪɢɛɟɞɟ ɠɢɿ
ɤɟɡɞɟɫɟɬɿɧ ɲɚɦɚɥɚɪɵ M 0 ɠԥɧɟ M S . Ȼɿɪɿɧɲɿ ɠɚԑɞɚɣɞɚ ɠԝɦɵɫɬɵԙ

ɮɨɪɦɭɥɚɫɵ A F ˜ S , ɚɥ ɟɤɿɧɲɿ ɠɚԑɞɚɣɞɚ ɠԝɦɵɫɬɵԙ ɮɨɪɦɭɥɚɫɵ A F ˜ S .

Ʉԛɲ ɠԝɦɵɫɵɧɵԙ ԧɥɲɟɦɞɟɪɿ: ɋɂ ɠԛɣɟɫɿɧɞɟ – ɤȽ ˜ ɦ2 / ɫ2 . Ȼԝɥ ɠԛɣɟɞɟɝɿ
ɠԝɦɵɫɬɵԙ ɛɿɪɥɿɤ ɲɚɦɚɫɵ ɞɠɨɭɥɶ (1Ⱦɠ 1ɇ ˜1ɦ ), ɚɥ ɬɟɯɧɢɤɚɥɵԕ ɠԛɣɟɞɟ –

ɤɢɥɨɝɪɚɦɦ-ɦɟɬɪɦɟɧ ԧɥɲɟɧɟɞɿ (1Ⱦɠ 0,102ɤȽɫ ˜ ɦ ɠԥɧɟ 1ɤȽɫ ˜ ɦ 9,81Ⱦɠ ).

3.4. ɌɟΝ Ωɫɟɪ ɟɬɭɲɿ ɤΟɲɬɿΝ ɠΡɦɵɫɵ ɬɭɪɚɥɵ ɬɟɨɪɟɦɚ. Ɍԥɠɿɪɢɛɟɞɟ ɬɟԙ
ԥɫɟɪ ɟɬɭɲɿ ɤԛɲɬɿԙ ɠԝɦɵɫɵɧ ɚɧɵԕɬɚɭ ɠɢɿ ɤɟɡɞɟɫɟɞɿ. Ɉɫɵԑɚɧ ɛɚɣɥɚɧɵɫɬɵ,
ɤɟɥɟɫɿ ɬɟɨɪɟɦɚɧɵ ԕɚɪɚɫɬɵɪɚɣɵԕ: ɧΟɤɬɟɧɿΝ ɛɟɥɝɿɥɿ ɛɿɪ ɨɪɵɧ ɚɭɵɫɬɵɪɭɵɧɞɚΕɵ

ɨΕɚɧ ɬΟɫɿɪɿɥɝɟɧ ɬɟΝ Ωɫɟɪ ɟɬɭɲɿ ɤΟɲɬɿΝ ɠΡɦɵɫɵ ΙΡɪɚɭɲɵ ɤΟɲɬɟɪɞɿΝ ɫɨɥ
ɨɪɵɧ ɚɭɵɫɬɵɪɭɥɚɪɵɧɞɚΕɵ ɫΩɣɤɟɫ ɠΡɦɵɫɬɚɪɵɧɵΝ ɠɢɵɧɵɧɚ ɬɟΝ ɛɨɥɚɞɵ.

oo o
Ԕɨɡԑɚɥɵɫɬɚԑɵ ɧԛɤɬɟɝɟ ɬԛɫɿɪɿɥɝɟɧ F1 , F2 , . . ., Fn ɤԛɲɬɟɪɿɧɿԙ ɬɟԙ ԥɫɟɪ

o oo o
ɟɬɭɲɿ ɤԛɲɿ F ɛɨɥɫɵɧ, ɹԑɧɢ F ¦ Fs . Ɉɫɵ ɬɟԙɞɿɤɬɿԙ ɟɤɿ ɠɚԑɵɧ dr

o oo

ɲɚɦɚɫɵɧɚ ɫɤɚɥɹɪ ɬԛɪɿɧɞɟ ɤԧɛɟɣɬɟɦɿɡ, ɫɨɧɞɚ: F˜ dr ¦ Fs ˜ dr ( dr – ɧԛɤɬɟɧɿԙ

ɷɥɟɦɟɧɬɚɪ ɨɪɵɧ ɚɭɵɫɬɵɪɭɵɧɵԙ ɜɟɤɬɨɪɵ). Ȼԝɥ ɬɟԙɞɿɤɬɿ M1 ɠԥɧɟ M 2
ɧԛɤɬɟɥɟɪɿ ɚɪɚɥɵԑɵ ɛɨɣɵɧɲɚ ɢɧɬɟɝɪɚɥɞɚɣɦɵɡ, ɛԝɥ ɤɟɡɞɟ:

M2 o o M2 o o M2 o o

³ F ˜ dr ³ Fs ˜ dr ¦ ³ Fs ˜ dr .
M1
M1 M1

Ⱥɥɵɧԑɚɧ ɬɟԙɞɿɤɬɿԙ ɫɨɥ ɠɚԑɵɧɞɚ ɬɟԙ ԥɫɟɪ ɟɬɭɲɿ ɤԛɲɬɿԙ, ɧԛɤɬɟɧɿԙ Ɇ1Ɇ 2
ɨɪɵɧ ɚɭɵɫɬɵɪɭɵɧɚ ɫԥɣɤɟɫ ɠԝɦɵɫɵ, ɚɥ ɨԙ ɠɚԑɵɧɞɚ – ԕԝɪɚɭɲɵ ɤԛɲɬɟɪɞɿԙ
ɫɨɥ ɨɪɵɧ ɚɭɵɫɬɵɪɭԑɚ ɫԥɣɤɟɫ ɠԝɦɵɫɵ, ɞɟɦɟɤ:

Ⱥ ¦ Ⱥs . (127)

ɋɨɧɵɦɟɧ, ɬɟɨɪɟɦɚ ɞԥɥɟɥɞɟɧɞɿ.
3.5. Ʉɟɣɛɿɪ ɠɚΕɞɚɣɥɚɪɞɚΕɵ ɠΡɦɵɫɬɚɪɞɵ ɟɫɟɩɬɟɭ. Ɍԥɠɿɪɢɛɟɞɟ ɠɢɿ

ɤɟɡɞɟɫɟɬɿɧ ɠɟɤɟɥɟɧɝɟɧ ɠɚԑɞɚɣɥɚɪɞɚԑɵ ɠԝɦɵɫɬɚɪɞɵ ɟɫɟɩɬɟɭɞɿԙ
ɮɨɪɦɭɥɚɥɚɪɵɧ ɤɟɥɬɿɪɟɣɿɤ.
– ɋɚɥɦɚԕ ɤԛɲɿɧɿԙ ɠԝɦɵɫɵ

A P ˜ (z1 z2 ) , (128)

ɮɨɪɦɭɥɚɞɚԑɵ z1 z2 – ɧԛɤɬɟɧɿԙ ɨɪɵɧɞɚɪɵɧɵԙ ɤԧɥɞɟɧɟԙ (ɝɨɪɢɡɨɧɬɚɥɶ)
ɠɚɡɵԕɬɵԕɬɚɧ ɚɪɚԕɚɲɵԕɬɵԕɬɚɪɵ (40-ɫɭɪɟɬ).

ȿɝɟɪ H z1 z2 ɞɟɩ ɛɟɥɝɿɥɟɫɟɤ, ɨɧɞɚ:

A rP˜ H (128-ɚ)

225